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Which game to play? in General
Electric Sheep One
Member # 3431
Profile #35
I prefer the Geneforge series, and since it's one long story, I'd recommend starting from the beginning. The first game in the series is probably the best of the first three, too, though in my opinion not by so much. G2 added some interesting new developments, including more artifacts, spells, and monsters. G3 wasn't a major breakthrough, but I thought it was a fine game, and it added some important elements.

G4 will be excellent. So you'd better hurry to get through the others!

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Posts: 3335 | Registered: Thursday, September 4 2003 07:00
"Turn al on" ...why? in Geneforge Series
Electric Sheep One
Member # 3431
Profile #19
That's why it's so impressive that I use only really dumb strategy. Phear my mad stupidness skillz!

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Posts: 3335 | Registered: Thursday, September 4 2003 07:00
Mac Users: Post Your Dashboard in General
Electric Sheep One
Member # 3431
Profile #72
I remember lsass.exe used to be something about license authority or some such. It would periodically go berserk and start consuming RAM rapidly, and I'd have to reboot.

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Posts: 3335 | Registered: Thursday, September 4 2003 07:00
No Harm Done: The Question of Morality in General
Electric Sheep One
Member # 3431
Profile #68
I was just trying to raise a principle that you seemed not to be recognizing. Maybe we can agree that if everyone around you is swearing, it's cool, and the few offended people shouldn't have come in if they didn't want to hear that kind of thing. If the proportions present go the other way, though, it's wrong to swear. Not terribly wrong, but still immoral. And if the proportions are roughly equal, both groups of people ought to exert themselves to tolerate each other.

When I was in college I was also in the army reserve. While at school I wouldn't split an infinitive in my thoughts, but after a day in the field on a training exercise, my language started to deteriorate. After two days it went right to —. Though I never went quite as far as the guys who used four letter words as punctuation. Some of those guys could command attention by suddenly not swearing.

The principle is that in something as insignificant as vocabulary you should respect the prevailing local standards, whatever they are.

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Posts: 3335 | Registered: Thursday, September 4 2003 07:00
Mac Users: Post Your Dashboard in General
Electric Sheep One
Member # 3431
Profile #11
Is that really true, about rebooting XP that often? I thought that was just Mac hype, since I didn't really have all that much trouble with needing restarts when I was running Windows 2000 Professional some years ago, and I heard XP was more stable than it was.

And I have had to restart Mac OS X. A few times, I think, over the past four years, apart from OS updates; and those cases were back in 10.2. 10.4 is indeed pretty darn stable.

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Posts: 3335 | Registered: Thursday, September 4 2003 07:00
Mac Users: Post Your Dashboard in General
Electric Sheep One
Member # 3431
Profile #7
Dashboard is funny. Very useful, but not quite how I expected, somehow. I end up having a few little utilities that I use regularly, like weather and a German dictionary, which could just as easily run normally but would bother me if they were cluttering up my Dock.

Stuff that is basically just launching a web browser for me turns out to be a pointless waste of memory, so I ditched the Wikipedia widget and stuff like that. For a while I had a lot of to-do list kinds of things, but I ended up just using iCal a lot instead.

A few games or amusements are okay.

Stickies are great, since they're immediately accessible but normally out of my face.

But my current favorite, and replacement for most of my Stickies, is iClip Lite. It's a long row of clipboard storage slots, with little thumbnail portholes to see what's in them. It looks nice and works simply, and it's a great tidy way of stashing pretty much anything for quick later retrieval.

Anybody try Yahoo Widgets? Several of them seemed to look nicer than most Dashboard widgets, but of these the nicest turned out to be brutal resource hogs, and although they eventually got fixed, somehow the trouble of running two widget systems at once never seemed justified.

I'm looking forward to the multiple desktops of Leopard. I always used to like this feature in KDE and Solaris.

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Posts: 3335 | Registered: Thursday, September 4 2003 07:00
No Harm Done: The Question of Morality in General
Electric Sheep One
Member # 3431
Profile #63
Nice how that works.

Objectivism versus relativism is something like a false dichotomy. Sure, literally they're exclusive. But all the impressive features I can see in relativism can be stolen by objectivism, if it is tempered with humility about one's own perception of truth, and sophisticated in considering moral questions in social context.

And I see nothing inconsistent about being objectivist about a few core principles, and broad-mindedly relativist about everything else. In this way I think it can be perfectly consistent to say that my culture's appreciation of the validity of other cultural attitudes is one of the things that makes my culture better than others.

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Posts: 3335 | Registered: Thursday, September 4 2003 07:00
No Harm Done: The Question of Morality in General
Electric Sheep One
Member # 3431
Profile #51
quote:
Originally written by The Almighty Do-er of Stuff:

Putting aside that this is a slippery slope fallacy, it is just a good an argument, if not better, for controlling one's anger as it is for not swearing. If a man cannot even keep himself from becoming angry at meaningless words, how can he control himself when something really maddening comes along?
Raising a slippery slope issue is not inherently fallacious. Slippery slopes exist. You've got to show that the slope is in fact not slippery in the case discussed. Then you can cry fallacy.

In the example of swearing, I'd agree with you in a case with two people. But what if many people want not to hear certain words? Why should the many have to change just to indulge the whims of one?

Apart from the argument, swearing is a fascinating social phenomenon. In French Quebec, the taboo words are the names of the objects involved in holy communion. 'Chalice!' will make grande-mère faint.

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Posts: 3335 | Registered: Thursday, September 4 2003 07:00
No Harm Done: The Question of Morality in General
Electric Sheep One
Member # 3431
Profile #29
I have no interest in defending whatever particular doctrines you were taught. To me CCD is a camera technology.

But I think your basic theory of morality is missing some important points.

One is that on little matters like swearing, the preferences of the many can outweigh the freedom of the one, no matter how irrational these preferences may be. If everyone in some village hates yellow, it's obnoxious for a stranger to go around waving yellow flags in their faces, no matter how innocent yellow may be in absolute terms. Obviously there are limits to this principle, but it seems to me that it does have some weight, which you neglect.

More importantly, a lot of traditional morality that deals with minor but common issues is based on a 'broken windows' theory. (This is the theory of community policing, which says that arresting vandals prevents drive-by shootings, and for which there seems to be some evidence.) In the Christian case this goes back to Jesus's frequent statement that 'the one who is faithful in little things will be faithful in big things'. Letting little things slip by fosters a mental climate, in one's own conscience if nowhere else, in which bigger and bigger things become easier and easier. So you need to use the little things to build your own integrity.

Immanuel Kant (I believe) called obligations like this 'imperatives of skill'. It's not that the thing itself is important, but that its training effect on the individual is necessary for achieving important things. Again, this is a principle whose implications must be balanced reasonably against those of other principles, but I think it's a principle that needs to be included in any serious morality. It's not enough to have the good intention of doing no harm. You have to work on developing and maintaining the character that you'll need, in case you ever have to live up to that intention under intense pressure.

That having been said, it certainly seems to me that obsession with minor sins can have as big a bad training effect, in the way of misery and confusion, as any good effect it may have. There is definitely a place for Martin Luther's notorious advice to 'sin boldly'.

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Posts: 3335 | Registered: Thursday, September 4 2003 07:00
Physics conundrums in General
Electric Sheep One
Member # 3431
Profile #44
If you don't like physics, just think: every instant of your life, the electromagnetic fields and waves that are penetrating your brain, and every particle in the air you breathe, and in your entire body, are all practising physics, whether you like it or not!

Otherwise, I'm thinking about some of the above posts.

[ Saturday, October 14, 2006 07:14: Message edited by: Student of Trinity ]

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Posts: 3335 | Registered: Thursday, September 4 2003 07:00
Physics conundrums in General
Electric Sheep One
Member # 3431
Profile #36
This is the point of my conundrums, apart from whatever interest they have as individual puzzles. There are different levels of description, for instance angular momentum and torque for rigid bodies versus momentum and force for particles, or pressure and streamlines for a fluid versus free motion and collisions for particles.

Having different levels of description is a profound thing in general, of course. Introducing a new level that actually works is one of the basic intellectual achievements. Like most other fields, physics is quite happy with having different levels of description. Where physics is perhaps special is that we insist that all levels be understood in terms of the bottom one. In practice we cannot always achieve that goal, but that is the goal. Higher levels of description are not autonomous in physics. To the extent that they are, one has ceased to do physics.

This does not mean that one must do every calculation in the most fundamental terms possible. It means that one should understand qualitatively whatever is going on in fundamental terms, and only rely on the higher level theory as an approximation technique for getting precise numerical values. So when one encounters a problem that one cannot answer even qualitatively in fundamental terms, this is a failure.

EDIT: This was written before 2bit's last post. As an addendum to react to that as well, I could mention that Einstein once cheerfully admitted that he did not know the speed of sound in air. He observed, though, that it was a simple fact which anyone could simply look up. What Einstein certainly must have known, however, was the basic idea of what sound is and how it propagates, in terms of molecular motion.

It is important that somebody is able to compute the precise speed of sound, and it would probably be good for everybody to do it once. It is not important to remember what it is forever after. But it is important to remember the conceptual relationship between molecules and sound. This is something basic and profound, an example of an enormous class of things in physics. Forgetting such a thing would be severe damage.

[ Friday, October 13, 2006 06:25: Message edited by: Student of Trinity ]

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Posts: 3335 | Registered: Thursday, September 4 2003 07:00
Physics conundrums in General
Electric Sheep One
Member # 3431
Profile #30
2bit: by 'particles' I guess you mean 'fluid elements' or something like that; in usual terminology, 'molecule' and 'particle' are interchangeable in the context of gas dynamics. No you don't need to be a piano tuner to make music. But theoretical physics is the lowest level science. Our instrument is maybe more like a guitar or a violin than a piano. And to play a violin well, you do need to know how to tune it.

I don't think you really can understand QCD without also understanding how a trebuchet works. In fact the QCD theta-vacuum involves stuff that's mathematically just like a trebuchet; but that's sort of a fluke, and not really a good counterargument to Kelandon's argument in general. The more serious point, I think, is that the theory of a trebuchet isn't that hard to absorb; if you come at all near it, you kind of can't avoid picking it up in passing. And come near it you will, because the first starting point towards QCD will be the harmonic oscillator, and soon after that, the physical pendulum as an anharmonic oscillator. QCD is an uncountable number of trebuchets, all hooked up together in tricky way, and quantized.

Physics really isn't very modular. Specialized and advanced stuff diverges, but everybody shares the same base, and the base stays active. You still use the stuff you learn in freshman year, forever afterwards. There's a good bit of F = m a even in string theory.

Now it's true that the people who can't explain why a spinning top precesses mostly manage to do other good work nonetheless. But it bugs people when they realize this is something they thought they understood, and they realize they don't. I think most people in physics do feel that they should be able to answer my five questions, even if they can't.

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Posts: 3335 | Registered: Thursday, September 4 2003 07:00
G3 decison on who to join up with in Geneforge Series
Electric Sheep One
Member # 3431
Profile #5
You can only bring one of Alwan or Greta past Dhonal, but you can still change sides after that. You should certainly play the game at least twice.

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Posts: 3335 | Registered: Thursday, September 4 2003 07:00
Physics conundrums in General
Electric Sheep One
Member # 3431
Profile #24
quote:
Originally written by 2bit:

The upper surface of an airplane wing has a greater radius of curvature than the lower surface. So, air flowing over (or molecules) follow a more curved path than those flowing under. this is what I was referring to. The particle "reacts" to the different curvatures of the wing's surfaces by taking different shaped paths when flowing past the two surfaces.
This is sort of right, I think, but it has a big problem. (Apart from the radius of curvature typo. The lower surface is indeed flatter, which means it has the larger radius of curvature.) Molecules do not feel pressure, any more than shopkeepers feel GNP. Pressure is a concept that only makes sense for large numbers of particles treated collectively. Individual molecules do not follow the streamlines of hydrodynamics, and do not simply 'flow past' the wing surfaces.

What molecules feel is other molecules. In a dilute gas like air, molecules are essentially never actually touching each other; but they very briefly collide and bounce away from each other, exchanging momentum and kinetic energy. At normal atmospheric pressure and room temperature, the typical molecule hits another one after travelling about a micron. And at a typical speed of 300 meters per second (the speed of sound, not coincidentally) this happens every few nanoseconds.

From these facts one can derive hydrodynamics as an accurate description of the collective behavior of the molecules on length scales much greater than a micron, and time scales much longer than a nanosecond. But what I want is to undo this derivation enough to understand just how and why molecules end up hitting the underside of the wing harder than the upperside.

In a sense this is random thermal motion doing all the lift; but not exactly. (Brownian motion is technically the motion of small but visible objects being hit by molecules, not the motion of the molecules themselves.) An airplane that is not moving forward does not float in midair; and airplane with an upside down wing would be in trouble, too. The combination of the wing shape and forward motion induces a general tendency for the randomly moving molecules to hit the lower surface of the wing more and/or harder. This is what I want to have explained.

Why is this stuff worth knowing? In one way, it is directly related to major unsolved problems. Ever since Boltzmann, the ideal gas has been a sort of paradigm system for the so-called arrow of time. It's not that dilute gases are responsible for my inability to remember tomorrow, but that they seem like the simplest system in which we might try to understand the emergence of time asymmetry in complex systems. Unfortunately we're not very close yet. The Boltzmann equation simply puts in this asymmetry by hand, and we have yet to truly explain it even in ideal gases.

Otherwise, physics is all about the buck stopping here. We're supposed to be able to explain everything from first principles; we're not a bunch of engineers who turn out working products without necessarily understanding our own tools. And the impulse that makes a physicist go, "Hey! Why can't I explain that precessing top?" is precisely the same emotion that makes them try to explain things that no-one can yet explain. It's kind of like how you can get a real athlete keenly interested in practically any game of physical skill, even if it's a professional basketball player playing shuffleboard. It's not a matter of the specific tasks they need for their job; it's a matter of the general mentality they need for their job.

My own research can be described as the middle ground between quantum information theory, condensed matter theory, and quantum optics. 10 years ago this would have been practically an empty set, but these days it is one of the hottest fields in physics, thanks to the development of techniques for trapping small samples of gas and cooling them to insanely low temperatures. It turns out that this gives us, in effect, designer matter. So you can take a whole slew of profound questions, and realistically contemplate putting them into the laboratory with all the confusing and irrelevant junk that usually clouds the issues stripped away.

The field is usually called 'cold atoms', or 'ultracold atoms', even though strictly speaking it is not the coldness of the individual atoms, but of the gases they make up, that is important and new. We should call it either 'cold gases' or 'slow atoms'. Anyway, I do theoretical calculations about this stuff, then try and talk experimentalists into doing hard experiments. Or I look at their data and try to figure out what is going on.

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Posts: 3335 | Registered: Thursday, September 4 2003 07:00
Physics conundrums in General
Electric Sheep One
Member # 3431
Profile #19
Well, who wants rubes? I've sometimes wondered whether wikis would be a good way to do research, but there are so many crackpots out there, that I figure I'd have to put in some sort of mini-exam as a password. Kind of 'let no-one ignorant of geometry enter here', and we really mean it.

About drag balancing gravity: this is what defines terminal velocity, which as I said above, is very slow for tiny drops. It would take me too much thought for tonight to calculate it, but I've watched sprayed mist fall. It's slow. So yes, I think this is why clouds don't fall. They do, but very slowly, and they fall relative to the air in which they are spread, which may well be rising.

I still give the prize to 'Suction!'. It's an answer that will do nicely to keep out the rubes.

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Posts: 3335 | Registered: Thursday, September 4 2003 07:00
Physics conundrums in General
Electric Sheep One
Member # 3431
Profile #16
Water has a pretty nearly fixed density, and for fixed density, mass is directly proportional to volume. No matter how small a water drop may be, it will not be held up against gravity by its buoancy in air.

[ Wednesday, October 11, 2006 11:23: Message edited by: Student of Trinity ]

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Posts: 3335 | Registered: Thursday, September 4 2003 07:00
Physics conundrums in General
Electric Sheep One
Member # 3431
Profile #14
Gas temperature is just local average of molecular kinetic energy; for fixed temperature, pressure is just a surrogate for density of molecules; fluid velocity is just a local average of molecular velocities. In terms of equations, I guess I'm really not going to be happy with anything higher level than the Boltzmann equation. But if you can give a conceptual explanation in terms of molecules that's really clear and convincing, that would be great.

EDIT: What do you mean by particles reacting to the wing's shape without ever touching the wing? There's a sense in which this true, but that's not exactly the way I would put it, because it also sounds like something crazy.

[ Wednesday, October 11, 2006 11:18: Message edited by: Student of Trinity ]

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Posts: 3335 | Registered: Thursday, September 4 2003 07:00
Physics conundrums in General
Electric Sheep One
Member # 3431
Profile #12
Was Latour by any chance a biologist by training? A lot of philosophers of science were trained as scientists at some point, but it's the blind men and the elephant. Anyway, I'm a theoretical physicist. A widget that's a black box isn't a tool, to me; it's a problem, no matter how well it works. Perhaps at some level everyone just accepts things; for instance, I use integrals all the time, but I have no idea what a Lebesgue measure is. At least I know Riemann's theory of integration, though.

When I figured out how levers really work, in terms of stress and strain tensors in finitely rigid rods; or when I figured out that a Newton's cradle is always a sequence of two-body collisions, because of the finite speed of sound in steel; I had a very satisfying feeling of, Aha! So that's what's going on! Physics at least is pretty much entirely about reductionism. Finding a black box widget that reproduces what happens is only the very first step.

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Posts: 3335 | Registered: Thursday, September 4 2003 07:00
Physics conundrums in General
Electric Sheep One
Member # 3431
Profile #10
About 1 I'm afraid I'm not really any better than Aran's and Alorael's answers. Yes, it must be that molecules hit the bottom of the wing harder than the top, and presumably this is because the plane is moving. But I'm pretty sure there's more to efficient aerodynamic lift than just being a kite. Wings have a particular shape, and this is supposed to be important. I should really sit down to think about this properly sometime.

About 2, the best answer I ever got was from an army officer who immediately answered, "Suction!", and then escaped while I was still stunned. The water droplets that make up clouds are very small, and have a very low terminal velocity, so they don't fall very fast. Updrafts and downdrafts are probably a bigger factor in the vertical motion of clouds than gravity. This is hand-waving, though. I believe the comparatively enormous amounts of energy involved in water condensation and evaporation can have huge effects on air temperature and pressure, so the hydrodynamics of clouds is formidable. Someday I'll get time to read a proper atmospheric physics text, and become happy.

4 and 5 I actually believe I understand, and I have some idea what the answer to 3 should look like. All of these are questions that many people do understand, of course; but they are a small minority even among physicists. The central issue in all of them is the role of what is called an effective theory. The fundamental theory is known -- in these cases, Newtonian mechanics -- but explaining things in these terms can be long and involved, like writing a program in machine language. From it people have derived higher level theories, which are powerful in the sense that they compress long explanations into short ones.

The problem is that some kind of information is always lost in going to the higher level explanation. Richard Feynman pointed out long ago that the ultimate higher level explanation is simply the equation "U=0", where U is the "unreality". This is very compact, but it's obviously a lousy explanation. Just what's lousy about it, though, is sort of hard to state clearly. What I want to say is that it conveys no understanding, but since I can't explain what understanding is, this is really not much better than just calling it lousy.

An objective measure of what gets lost with effective theories, though, is simply that hardly any physicists can explain why a spinning top precesses, without using the words 'angular momentum'. Yet all trained physicists know that angular momentum is a derived quantity in classical mechanics, so that any statements about angular momentum and torque are in principle reducible to statements about linear momentum and force. They just can't actually perform the reduction, though they should be able to and know they should be able to, in the practical case of a spinning top.

This seems to me to be an interesting case study for the philosophy of science.

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Posts: 3335 | Registered: Thursday, September 4 2003 07:00
Physics conundrums in General
Electric Sheep One
Member # 3431
Profile #0
Non-physics conundrum: Could the plural really be 'conundra'? That sounds almost too good to be true.

Anyway, here are some questions that I have asked a lot of physicists over the years, and mostly stumped them. I think I understand them myself to varying degrees, but few well enough to make me really happy. They're nothing very advanced, but they have a common feature that I think is really profound.

1) How do airplanes really fly? The answer must be in terms of molecules bouncing off the wings, and not in terms of hydrodynamics! Lots of people know some pat answer about Bernoulli's principle. That's not what I want.

2) What keeps clouds up? They're made of water droplets, not vapor, and water is heavier than air. So why don't clouds all fall? Actually, for a start I'd be happy for a hydrodynamic answer to this one. But ultimately I want a molecular story here, too.

3) Why does a tilted spinning top precess instead of falling over? Your answer must be entirely in terms of force and acceleration; you must not invoke angular momentum. In classical mechanics, angular momentum and all its properties are not fundamental, but derived; so everything must follow from Newton's Laws alone.

4) Related to 3), and a bit easier: Derive the 'law of balance' for the equilibrium of a lever, M1 L1 = M2 L2, in terms of force alone, without invoking torque or angular momentum.

5) The rule for a 'Newton's Cradle' is the number of balls swinging in is the number that bounce out. Explain why this is, after realizing that conservation of energy and momentum only works for the case of two balls. With as few as three balls, the conservation laws also allow additional solutions, which one does not see in reality.

If anyone knows any further questions in this spirit, I'd be very happy to add them to my list.

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Posts: 3335 | Registered: Thursday, September 4 2003 07:00
Dingaling on a donut (Ver Z) in General
Electric Sheep One
Member # 3431
Profile #1
Somehow I read 'dingaling' as a participle and thought, "Is that what he's doing, then, dingaling?" I almost got as far as googling 'dingal' to see what it was all about.

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Posts: 3335 | Registered: Thursday, September 4 2003 07:00
Notice : Uber popular mod needs maid in General
Electric Sheep One
Member # 3431
Profile #5
See, this is how the Borg gets started.

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Posts: 3335 | Registered: Thursday, September 4 2003 07:00
I Am Engaged in General
Electric Sheep One
Member # 3431
Profile #30
According to some old family wisdom my father passed along, the classic four things to be sure to agree on are religion, politics, money, and children. Agreement on them doesn't make for any great romantic glow or anything, but disagreement usually doesn't get worked out over the years, and once people get old enough to realize they won't have infinitely many chances to get what they want out of life, these issues become crises.

So at least one of the four is down for Alec. Congratulations on your engagement; enjoy it, too. Being engaged is nice in that the whole world does seem to be congratulating you all the time for this wonderful special thing. Getting married is in one way a let-down, in that suddenly you're not so special. Otherwise worth it, though.

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Posts: 3335 | Registered: Thursday, September 4 2003 07:00
Factions in Geneforge Series
Electric Sheep One
Member # 3431
Profile #33
Though all of this is whistling in the dark, since we understand little about either intelligence, in the abstract, or the brain.

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Posts: 3335 | Registered: Thursday, September 4 2003 07:00
The Doomsies in General
Electric Sheep One
Member # 3431
Profile #6
It's the ones who aren't conspiring that you have to watch, because theirs are the undetected conspiracies.

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Posts: 3335 | Registered: Thursday, September 4 2003 07:00

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